Erasmus caemmeree



(No Model.)

B. GAEMMERER. MOUNTING FOR COMMUTATORS 0F DYNAMO ELECTRIC MACHINES.

Patented Sept. 14

MMMMWI Qrwmarag UNITED STATES PATENT OFFICE.

ERASMUS CAEMMERER, OF CHICAGO, ILLINOIS, ASSIGNCR TO THE SIEMENS & IIALSKE ELECTRIC COMPANY OF AMERICA, OF SAME PLACE.

MOUNTlNG FOR COMMUTATORS OF DYNAMO-ELECTRIC MACHINES.

SPECIFICATION forming part of Letters Patent No. 590,000, dated September 14, 1897.

Application filed May 18, 1897. serial No. 636,348. (No model.)

To all whmn it may concern: and Fig. i is a similar view showing upon an Be it known that I, ERASMU s CAEMMERER, enlarged scale the mounting for the com mua subj ect of the Emperor of Germany, residing tater-frame. at Chicago, in the county of Cook and State of Likelettcrs refer to like parts in both views. 55 Illinois, have invented new and useful Im- The dynamo shown has fields a a stationprovementsin Mountings for Commutatorsof arily mounted within the ring armature b. Dynamo-Electric Machines, of which the fol- The armature is secured at the ends of a plulowing is a specification. rality of radial arms 0 of a spider c, which is Myinvention relates to an improved mountkeyed to the main shaft (Z and rotatably 60 [0 ing for commutators of dynamo-electric mamounted in bearings d (1. Midway upon a chines, and has for its object the protection portion of the radial arms 0 are provided of the machines from injury due to short-ciropenings which are adapted to receive studs euiting and static discharges. or posts 6 of the commutator-frame f, an in- A difficulty frequently met with in the opsulating-bushing e and washer e being inter' 65 eration of dynamos of the usual construction posed between the metal surfaces at each is the short-circuiting of current at the compoint of connection. The studs care secured mutator and consequent burning out of the to the commutator-frame by taper-bolts f. insulation between said commutator and the A recessed portion is provided upon said comframe of the machine. This may result mutator-frame which receives aninsulating 7o either from static discharges or from the flash band and ring g 9', wherein are disposed the occurring at the brushes when the circuitcommutator-bars 7b. The brushes of the mabreaking device is actuated to open the eirchine are carried upon the brush-supports 2'. cuit, causing the current to are over the in- From the above it will be seen that in addisulation of the commutator to the frames of tion to the insulation provided between the 75 said commutator and dynamo. Especially is surfaces of the commutator and its frame the this found true of railway-generators, which said frame, which, preferably, is connected ordinarily are designed to furnish heavy curwith the arms of the spider at comparatively rents and are connected to ground. In such few points of support, has supplementary inmachines an accident of this class is liable to sulation interposed at these points, which ef- 8o be of a serious nature, since a short circuit fectually prevents the flashing over or shortfrom the ungrounded pole to the frame of the circuiting of the current at the commutator machine and thence to ground will often burn with its attendant danger to the machine. out the commutator or result in even more The commutator and its supports are not serious damage. Moreover, this type of gensubjected to any considerable strain even in 85 3 5 erator, because of the large surface of con the larger type of machines. Hence the conductor presented to the grounded commutanections with the arms of the spider may tor-frame, offers a large condenser-so.rface, safely be lessened in number to secure the which greatly increases the danger of lightreduction of contiguous metallic surfaces. ning discharges through the insulation. Having now described my invention, what 90 My invention consists in interposing be- I claim as new, and desire to secure by these tween the commutator-frame and its support- Letters Patent, ising parts an insulating-mounting, preferably 1. The combination in a dynan'io-electric situated between the insulated parts, to semachine, with the comnmtator, of the comcure a minimum exposure of conducting-surmutator frame supporting said commutator 95 faces. but electrically insulated therefrom, and an I will describe my invention in connection insulating-mounting interposed between the with a dynamo provided with an external commutator-frame and the supporting part ring armature and internal fields by the aid of the dynamo-electric machine, substantially of the accompanying drawings, in which as described. too Figure l is a vertical sectional view of a 2. The combination with the fields and ardynamo in which my invention is utilized, mature of a d ynamo-electric machine of a eoininutator-frame mounted to rotate with said armature, commutator-bars provided upon and insulated from said frame, and an insulating-mounting provided between the said commutator-fraine and the supporting part of the dynamo, substantially as described.

In a dynamo-electric machine, the combination with the fields and armature thereof, of a connnutator-frame mounted to rotate with said armature, commutator-bars provided upon and insulated from said frame, and insulating-inountings interposed between the commutator and the supporting part of the dynamo at the points of support, the parts being constructed to reduce the exposure of conducting-surfaces at said points of support, substantially as described.

t. The combination with the fields and armature of a dynamo-electric machine, of a rotatable spider 0 upon which said armature is carried, a commutater-frame f, commutator-bars 7t mounted thereon and insulated from the Frame, studs e secui ed to said frame and the spider, and insulat hie-mountings c a" interposed between said frame and spider, substantially as described.

5. The combination in a dynamo-electric machine, with fields a, of an armature Z), a rotatable spider 0 upon the arms-of which said armature is mounted, acommutatorframe 1", commutator-bars lt mounted upon and insulated from said frame, studs 0 and insulating-111011ntings therefor provided for a portion of said spider-arms, adapted to be bolted to said connnutator-frame and secure it in position upon the spider, substantially as described.

In testimony whereof I ai'iix my signature, in the presence of two witnesses, this 2d day of April, 1897.

iltriSniiiS CAEMMERER.

Lil 

